Coffee machine



FIG. 1 is a front view of the coffee machine showing my design;

FIG. 2 is a right side view of the coffee machine showing my design;

FIG. 3 is a rear side view of the coffee machine showing my design;

FIG. 4 is a top plan view of the coffee machine showing my design; and,

FIG. 5 is a front perspective view of the coffee machine showing my design. 

The ornamental design for a coffee machine, as shown and described. 